Motivation

Fixes #2307

Proposed changes

• Manually add the module to sys before executing it
• I've also renamed insert_embed_line_to_module to insert_embed_line_to_module_and_exec to better reflect that this method is actually executing the user code. Please read over the docstrings again as I think they are outdated. I've added two lines beforehand to briefly describe what the method is actually doing.

Test

from dataclasses import dataclass
from manimlib import *


@dataclass
class Coordinates2D:
    x: float
    y: float


class MyScene(Scene):
    def construct(self):
        print("Hello, world!")

If you call this via

manimgl "./path/to/bug-test-file.py" MyScene -e 13

it should show "Hello, world!", instead of crashing like in #2307.